Whereas a mushroom soup in the West is typically a hearty affair, rich and filling, a mushroom soup in China is delicate and light. The stock is clear and the mushrooms float in strips on the top, garnished with a sprinkling of green. It is a simple bowlful, meant to be sipped throughout the meal as a beverage, or drunk at meal’s end to settle and soothe (though you may serve it as an opener if you like, in the spirit of a good consommé.)
Soak the dried mushrooms in 3 cups cold or hot water to cover until soft and spongy, 20 minutes to an hour. (You will get maximum flavor if the mushrooms are soaked in cold water several hours or overnight.) Snip off the stems with scissors, strain the soaking liquid to eliminate any sand, then put the stems and the strained liquid aside. Rinse the caps thoroughly to dislodge any sand trapped in the gills, then slice them into long slivers 1/16 inch thick.
Clean fresh mushrooms if required: Brush button mushrooms or bob them briefly in cool water; brush, wipe, or briefly rinse chanterelles (they are fragile, so avoid rinsing if you can); wipe shiitake. Enokitake do not require cleaning. Trim off and reserve the browned or ragged base of the stem, and cut button mushrooms into 1/16-inch thin umbrella-like slices. Reserve any trimmings from chanterelles, and cut them into thin slivers that will accentuate their pretty curves. Snip off and reserve shiitake stems, and cut the caps into long slivers 1/16 inch thin. Cut off and reserve the spongy base of enokitake where they are joined together, and gently separate the mushrooms into small groups. Cut off the base of oyster mushrooms if spongy or dry, reserve, and leave the smaller mushroom clusters intact.
Add the mushroom trimmings to the stems and strained liquid reserved from soaking black mushrooms. Bring to a boil in a small saucepan, simmer until reduced by half, then strain through several layers of wet cheesecloth. You will need 1 cup deeply flavored liquid. If you have more than 1 cup and the taste is pale, reduce it further.
If you are adding pork to the soup, cut it crosswise against the grain into thin slices ⅛ inch thick. Shred the slices against the grain into slivers ⅛ inch wide, then cut long slivers crosswise into 1¼-inch lengths. Blend the soy, wine, cornstarch, sugar, and sesame oil until smooth, and toss well with the pork. Seal airtight and refrigerate 30 minutes or overnight.
Combine the slivered dried black mushrooms, chicken stock, and 1 cup reduced mushroom liquids in a 2–2½-quart non-aluminum saucepan. Bring to a simmer, add fresh peas if you are using them, and cover the pot. Reduce the heat to low and keep the stock at a very gentle simmer while you stir-fry the fresh mushrooms.
Proceed immediately to heat a wok or a large, heavy skillet over high heat until hot enough to evaporate a bead of water on contact. Add 2 tablespoons com or peanut oil and 1 teaspoon sesame oil, swirl to coat the pan, and reduce the heat to medium to avoid burning the sesame oil. When the oil is hot enough to sizzle a bit of scallion, add the shallots and the scallion. Stir gently until fragrant, 10–15 seconds, adjusting the heat to maintain a merry sizzle without browning the shallots. When fully fragrant, add the wine, let the alcohol “explode” in a fragrant hiss, then immediately add the fresh mushrooms. Stir-fry about 4–5 minutes, or until soft, dribbling in more oil if necessary from the side of the pan. Use only as much oil as the mushrooms absorb; there should be no extra left in the pan.
When the mushrooms are soft, add them to the stock. Raise the heat to bring the mixture to a near-boil, then adjust to maintain a steady simmer. Cover, and simmer 5 minutes. Reduce the heat to low and taste the soup. Add the sugar, then season carefully with salt to bring out the full mushroom flavor. If you are working a day in advance, turn off the heat, let the soup cool under a cover, then refrigerate overnight.
Just before serving, return the soup to a simmer over moderate heat. If you are adding pork, stir the shreds with your fingers to loosen them, and slide them into the simmering stock. Stir gently until the meat turns gray, about 15 seconds. If you are adding defrosted peas, slide them in last, then stir several seconds to heat them through.
Serve the soup in heated bowls, portioning the many mushrooms evenly between them.
Leftovers keep beautifully 4–5 days and grow even richer with reheating.
© 1982 Barbara Tropp estate. All rights reserved.